Semiconductor manufacturing device, semiconductor manufacturing system and substrate treating method

ABSTRACT

A semiconductor manufacturing device having a buffer unit which receives a substrate treating substance from an external source, stores it therein, and delivers it to an external unit.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application is based on and claims the benefit of priorityfrom the prior Japanese Patent Application No. 2002-073,217 filed on oraround Mar. 15, 2002, the entire contents of which are incorporatedherein by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a semiconductor manufacturingdevice, a semiconductor manufacturing system, and a substrate treatingmethod, and more particularly relates to a semiconductor manufacturingdevice which comprises a source supplying substrate treating substancesto a substrate treating chamber, a semiconductor manufacturing systemwhich comprises at least a source supplying substrate treatingsubstances to a substrate treating chamber and a semiconductormanufacturing device, and a substrate treating method applicable to thesemiconductor manufacturing device and the semiconductor manufacturingsystem.

[0004] 2. Description of the Related Art

[0005] A semiconductor manufacturing device uses a variety of substancessuch as source gases, chemicals, and solvents in a semiconductormanufacturing process. Generally, such substances are supplied from asource which is located near a semiconductor manufacturing plant, andincludes cylinder cabinets, gas generators, chemical and solvent tanks,a refiner like an ion exchanger, and so on. The substances are deliveredto a semiconductor manufacturing device via gas delivery pipes, orchemical or solvent delivery pipes. The source has a capacity which issufficient to deliver the substances without any problem.

[0006] Further, the foregoing pipes are large enough to reliably deliverthe substances at a required speed.

[0007] The foregoing semiconductor manufacturing device or asemiconductor manufacturing system including such a semiconductormanufacturing device seems to have the following problems.

[0008] The substances such as source gases, chemicals and solvents arenot always consumed at the same speed in the semiconductor manufacturingdevice. For instance, an LPCVD (low pressure chemical vapor deposition)device produces polycrystalline silicon films on a plurality ofsemiconductor wafers using the LPCVD process of the batch processingtype, and requires a mono-silane gas as a source gas only during theformation of polycrystalline silicon films. No source gas is consumedfor evacuating substrate treating chambers, and loading or unloadingsemiconductor wafers to or from a shelf shaped port in the substratetreating chamber even when the LPCVD device is in operation. Thecapacities of the source or delivery pipes are designed on the basis offeed rates of the source gases which are being consumed. If ten LPCVDdevices were provided in the semiconductor manufacturing plant, thesource and delivery pipes would be required to have capacities fordelivering the source gases to them.

[0009] Further, coolants are also supplied to the LPCVD device in orderto cool heaters and pumps, which are used to control temperatures of thesubstrate treating chambers. A large amount of coolants should besupplied during the operation of the heaters while little coolants arenecessary during the non-operation of the heaters.

[0010] Still further, cleaning gases are supplied to the LPVCD device inorder to clean the substrate treating chambers, but are required onlywhen the treatment chambers are being cleaned.

[0011] Recently, semiconductor wafers are being enlarged in order tolead better productivity of semiconductors. In response to this trend, asemiconductor manufacturing device, e.g. a substrate treating chamber ofan LPCVD device, is also being enlarged, which means increases in sourcegases, chemicals or solvents to be consumed. Therefore, large sources ordelivery pipes are required in order to meet the foregoing requirements,which would lead to large capital investments.

BRIEF SUMMARY OF THE INVENTION

[0012] According to a first feature of the embodiment of the invention,there is provided a semiconductor manufacturing device comprising abuffer unit which receives a substrate treating substance from anexternal source, stores it therein, and delivers it to an external unit.

[0013] In accordance with a second feature of the embodiment of theinvention, there is provided a semiconductor manufacturing devicecomprising: a substrate treating chamber; and a buffer unit provided inthe substrate treating chamber or in the semiconductor manufacturingdevice, receiving a substrate treating substance from an externalsource, storing it therein, and delivering it to the substrate treatingchamber or the semiconductor manufacturing device for the purpose oftreating substrates.

[0014] As a third feature, the embodiment of the invention provides asemiconductor manufacturing system comprising: an external sourcesupplying a substrate treating substance; a semiconductor manufacturingdevice including a substrate treating chamber; a buffer unit receivingthe substrate treating substances from the external source, storing ittherein, and delivering it to the substrate treating chamber or thesemiconductor manufacturing device; and a control unit controlling thedelivery of the substrate treating substances from the external sourceto the buffer unit and the delivery of the substrate treating substancesfrom the buffer unit to the substrate treating chamber or thesemiconductor manufacturing device. The semiconductor manufacturingsystem further comprises a computer-integrated manufacturing (CIM)system which thoroughly manages the delivery of the substrate treatingsubstances from the external unit, the receipt and storage of thesubstrate treating substance in the buffer unit, and controls theoperations of the semiconductor manufacturing device and the controlunit.

[0015] The CIM system includes a record-keeping database which recordsand manages an in-service schedule of the substance treatment and amanufacture schedule, and controls at least a delivery speed or adelivery order of the substrate treating substances from the externalsource to the semiconductor manufacturing device via the buffer unit.According to a fourth feature of the embodiment of the invention, thereis provided a substrate treating method comprising: receiving asubstrate treating substance from an external source, storing in abuffer unit the substrate treating substance necessary for at least onesubstrate treating process, and delivering a predetermined amount of thesubstrate treating substance to a substrate treating chamber or asemiconductor manufacturing device provided with a substrate treatingchamber.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0016]FIG. 1 is a block diagram of a semiconductor manufacturing deviceand a semiconductor manufacturing system according to a first embodimentof the invention.

[0017]FIG. 2 is a block diagram showing a first control method forloading a substrate treating substance to a buffer unit in thesemiconductor manufacturing system of FIG. 1.

[0018]FIG. 3 is a block diagram showing a second control method forloading the substrate treating substance to the buffer unit.

[0019]FIG. 4 is a block diagram showing a third control method forloading the substrate treating substance to the buffer unit.

[0020]FIG. 5 is a block diagram showing a first control method fordelivering the substrate treating substance to a substrate treatingchamber from the buffer unit in the semiconductor manufacturing systemof FIG. 1.

[0021]FIG. 6 is a block diagram showing a second control method fordelivering the substrate treating substance to the substrate treatingchamber from the buffer unit in the semiconductor manufacturing systemof FIG. 1.

[0022]FIG. 7 is a block diagram showing a third control method fordelivering the substrate treating substance to the substrate treatingchamber from the buffer unit in the semiconductor manufacturing systemof FIG. 1.

[0023]FIG. 8 is a flow chart showing an operation sequence of thesemiconductor manufacturing system of FIG. 7.

[0024]FIG. 9 is a graph showing time-dependent variations of aconcentration of a mono-silane gas.

[0025]FIG. 10 is a graph showing time-dependent variations of depositionrate, thickness and speed of a polycrystalline silicon film on asemiconductor wafer in the semiconductor manufacturing system of FIG. 7.

[0026]FIG. 11 is a block diagram showing a control process for loading aliquid substance to the buffer unit in the semiconductor manufacturingdevice or semiconductor manufacturing system in the first embodiment.

[0027]FIG. 12 is a block diagram showing a control process for loading asolid substance to the buffer unit in the semiconductor manufacturingdevice or semiconductor manufacturing system in the first embodiment.

[0028]FIG. 13 is a block diagram of a semiconductor manufacturing deviceor a semiconductor manufacturing system in a second embodiment of theinvention.

[0029]FIG. 14 is a block diagram of a semiconductor manufacturing deviceor a semiconductor manufacturing system in a first modified example of athird embodiment of the invention.

[0030]FIG. 15 is a block diagram of a semiconductor manufacturing deviceor a semiconductor manufacturing system in a second modified example ofthe third embodiment of the invention.

[0031]FIG. 16 is a block diagram of a semiconductor manufacturing deviceor a semiconductor manufacturing system in a fourth embodiment of theinvention.

[0032]FIG. 17 is a block diagram of a semiconductor manufacturing deviceor a semiconductor manufacturing system in a modified example of thefourth embodiment of the invention.

[0033]FIG. 18 is a block diagram of a semiconductor manufacturing deviceor a semiconductor manufacturing system in a fifth embodiment of theinvention.

DETAILED DESCRIPTION OF THE INVENTION

[0034] The invention will be described with reference to embodiments ofa semiconductor manufacturing device, a semiconductor manufacturingsystem, and a substrate treating method shown in the drawings, wherelike or corresponding parts are denoted by like or correspondingreference numerals.

[0035] (First Embodiment of the Invention)

[0036] This first embodiment of the invention relates to a semiconductormanufacturing device 1 as an LPCVD device, a semiconductor manufacturingsystem including such a semiconductor manufacturing device, and asubstrate treating method applied to them.

[0037] [Basic Structure of Semiconductor Manufacturing Device 1 andSemiconductor Manufacturing System]

[0038] Referring to FIG. 1, the semiconductor manufacturing device 1uses a mono-silane gas as a source gas in order to form polycrystallinesilicon films on semiconductor wafers, and includes a substrate treatingchamber 2, and a buffer unit 4 which receives a substrate treatingsubstance from an external source 20, stores it therein, and delivers itto the substrate treating chamber 2 or to the semiconductormanufacturing device 1.

[0039] The term “substrate treating” denotes not only forming thinconductive or insulating films on semiconductor wafers (mainly made of aIII-V group elements), on glass substrates for a liquid crystal displayor the like, on insulating substrates used as wiring substrates, butalso etching films. The term “substrate treating substances” refers notonly to source gases, liquid chemicals or solvents, granular or solidsubstances which are directly used for treating substrates, but also tocleaning gases, liquid coolants and so on which are indirectly used fortreating the substrates. The external source 20 is provided outside thesemiconductor manufacturing device 1 and supplies the substrate treatingsubstances.

[0040] The semiconductor manufacturing device 1 further includes acontrol unit 6 which controls states of the substrate treatingsubstances in the buffer unit 4, and a measuring unit 5 which measuresthe states of the foregoing substances.

[0041] The semiconductor manufacturing device 1 is generally installedat an upper part (fab story) 101 of a clean room 100 in a semiconductormanufacturing plant. The substrate treating chamber 2 includes areaction tube 201 made of very pure quartz, and a port (without areference numeral) provided in the reaction tube 201 and receivingsubstrates such as semiconductor wafers. A heater 202 surrounds thereaction tube 201 in order to control a temperature thereof.

[0042] In this embodiment, the buffer unit 4 is housed in thesemiconductor manufacturing device 1, and is positioned between theexternal source 20 and the substrate treating chamber 2, receives thesubstrate treating substances from the external source 20, stores themtherein, and delivers a predetermined amount of them to either thesubstrate treating chamber 2 or to the semiconductor manufacturingdevice 1. The substrate treating substances are intermittently deliveredfrom the external source 20, and are temporarily stored in the bufferunit 4. The buffer unit 4 is made of quartz, metal or the like in orderto be resistant to the substrate treating substances and pressure and toimprove productivity, and is preferably in the shape of a tank having anappropriate capacity.

[0043] The external source 20 includes a mono silane gas cylinder 21, anitride gas generator 22, and a fluorine gas generator 23. Themono-silane gas cylinder 21 and nitride gas generator 23 are providedoutside the clean room 100. The mono-silane gas cylinder 21 supplies amono-silane gas to the buffer unit 4 via a pneumatic valve 702. Thenitride gas generator 22 supplies a nitride gas to the buffer unit 4 viaa pneumatic valve 703. The nitride gas is used to clean the buffer unit4 and the substrate treating chamber 2, and is also used as a dilutiongas while the substrate treating substance is reacted. Further, thenitride gas is used in order to return a pressure in the substratetreating chamber 2 to 1×10⁵ Pa. The fluorine gas generator 23 ispositioned in a sub-fab story 102 under the clean room 100, and suppliesa cleaning gas to the buffer unit 4 via a pneumatic valve 701. Thecleaning gas is used to etch and clean an inner wall of the substratetreating chamber 2 or silicon films on components made of quartz,silicon-carbide and so on.

[0044] The buffer unit 4 and the substrate treating chamber 2 areconnected by a pneumatic valve 801, through which the mono-silane gas,nitride gas or fluorine gas is delivered to the substrate treatingchamber 2 from the buffer unit 4.

[0045] The measuring unit 5 of the semiconductor manufacturing device 1is a pressure gauge, for instance, is connected to the buffer unit 4,and measures a pressure (states) of the substrate treating substance inthe buffer unit 4.

[0046] For instance, the mono-silane gas in the substrate treatingchamber 2 is heated by a heater 202 in order to form a polycrystallinesilicon film on a semiconductor wafer using the LPCVD reaction. Thefluorine gas cleans the inner wall of the substrate treating chamber 2by the etching reaction. After the LPCVD or etching reaction, reactedgases or non-used gases are discharged by a vacuum exhaust pump 30 via agate valve 802.

[0047] The gate valve 802 opens and closes in order to adjust a fluidconductance in the substrate treating chamber 2, and also interrupts thegas. The vacuum exhaust pump 30 is positioned in the sub-fab story 102in the cleaning room 100. An exhaust gas from the vacuum exhaust pump 30is purified in a purifier 31, and is discharged to the outside via anexhaust duct 32 in the sub-fib story 102.

[0048] The control unit 6 controls the operations of the heater 202,measuring unit 5, pneumatic valves 701 to 703 and 801, and gate valve802, which means that the control unit 6 controls the whole operationsof the semiconductor manufacturing device 1

[0049] Specifically, the control unit 6 is connected to a manufacturemanaging database 10 which manages data of the LPCVD process, to adevice managing database 11 which manages the operations of thesemiconductor manufacturing device 1, and to a an integrated in-plantbuffer controller 12. The control unit 6 is in connection with themanufacture managing database 10 and the device managing database 11 viaa local area network (called the “LAN”) 13 of the computer-integratedmanufacture control system (called the “CIM system”). The control unit 6receives outputs from a pressure gauge (not shown) and heater 202 in thesubstrate treating chamber 2, i.e. measured values such as a furnacepressure and temperature of the substrate treating chamber 2. Thecontrol unit 6 transfers film depositing information to the manufacturemanaging database 10 via the LAN 13.

[0050] The semiconductor manufacturing system is constituted by: thesemiconductor manufacturing device 1 which includes at least theexternal source 20 supplying the substrate treating substances and thesubstrate treating chamber 2; the buffer unit 4 which receives thesubstance treating substance from the external source 20, stores ittherein, and delivers it to either the substrate treating chamber 2 orthe semiconductor manufacturing device 1; and the control unit 6 whichcontrols the delivery of the substrate treating substances between theexternal source 20 and the buffer unit 4, and between the buffer unit 4and the substrate treating chamber 2 or the semiconductor manufacturingdevice 1.

[0051] [Operation of Semiconductor Manufacturing Device 1 andSemiconductor Manufacturing System, and Substrate Treating Method]

[0052] A polycrystalline silicon film will be deposited on asemiconductor wafer as described hereinafter by the semiconductormanufacturing device 1 and the semiconductor manufacturing system. Inthis case, the substrate is treated using the LPCVD process.

[0053] (1) First of all, the following LPCVD process data are input intothe control unit 6 from the manufacture managing database 10 via the LAN13, which is performed before raw semiconductor wafers are delivered tothe semiconductor manufacturing device 1.

[0054] a. thickness of the polycrystalline silicon film: 100 nm

[0055] b. film depositing temperature: 620° C.

[0056] c. feed rate of mono-silane gas: 100 sccm

[0057] d. film depositing pressure: 26.6 Pa

[0058] e. film depositing period: 10 minutes

[0059] A total amount of the mono-silane gas to be used is expressed bythe following formula.

100 sccm×10 minutes 1000 scc (i.e. a volume of 1000 cm³

[0060] under a standard state of a gas)

[0061] In this case, the buffer unit 4 has a 1000 scc capacity, forinstance.

[0062] (2) The control unit 6 opens the gate valve 802 once inaccordance with the received data, thereby evacuating the substratetreating chamber 2 to a sufficiently low pressure using the vacuumexhaust pump 30.

[0063] (3) Thereafter, the control unit 6 closes the gate valve 802, andopens the pneumatic valve 702, so that the mono-silane gas will bedelivered to the buffer unit 4 from the mono-silane gas cylinder 21.When the buffer unit 4 is filled with the 1000 scc mono-silane gas, thecontrol unit 6 closes the pneumatic valve 702. Therefore, the bufferunit 4 is sealed, thereby temporarily storing the mono-silane gas.

[0064] The mono-silane gas is filled into the buffer unit 4 by any ofthe following control methods shown in FIG. 2 to FIG. 4.

[0065] According to a first control method shown in FIG. 2, a pressureregulator 710 is provided between the mono-silane gas cylinder 21 andthe buffer unit 4, and in front of (or behind) the pneumatic valve 702,and automatically adjusts an amount of the mono-silane gas to besupplied to the buffer unit 4 in response to a command from the controlunit 6. The pressure regulator 710 is preferably a pressure controlvalve, and maintains a pressure of the mono-silane gas at 26.6 Pa, whichallows the buffer unit 4 to store the mono-silane gas in the amount of1000 scc.

[0066] With a second control method shown in FIG. 3, the amount of themono-silane gas to be supplied is controlled on the basis of a feed rateand a feed period thereof. A mass flow controller 711 is positionedbetween the mono-silane gas cylinder 21 and the buffer unit 4 and infront of (or behind) the pneumatic valve 702, and controls the amount ofthe mono-silane gas to the buffer unit 4. When the mono-silane gas issupplied for 30 seconds at the feed rate of 2 slm, the buffer unit 4 isfilled with 1000 scc mono-silane gas. Further, if an inexpensive massflow meter is used in place of the mass flow controller 711, the 1000scc mono-silane gas to the buffer unit 4 can be controlled on the basisof integrated output values of the mass flow meter. According to a thirdcontrol method of FIG. 4, the amount of the mono-silane gas iscontrolled on the basis of a pressure measured by the measuring unit 5attached to the buffer unit 4. When the measured pressure becomes equalto a predetermined value, the control unit 6 closes the pneumatic valve702, thereby controlling the amount of the mono-silane gas in the bufferunit 4. If the pressure of the mono-silane gas quickly increases, aconductance regulator 712 is preferably provided in front of thepneumatic valve 702 in order to feed-back control the amount of the monosilane gas on the basis of the measured pressure thereof. Theconductance regulator 712 may be an orifice, a piezzo valve or the likewhich opens or closes in order to adjust a conductance.

[0067] The pressure regulator 710, mass flow controller 711 orconductance regulator 712 which is rather expensive can be used incommon for a plurality of the semiconductor manufacturing devices 1 whenit is positioned in front of them, i.e. just behind the mono-silane gascylinder 21.

[0068] No mass flow controller 711 (or no mass flow meter) is employedin the first and third control methods (shown in FIG. 2 and FIG. 4,respectively). However, since the inner capacity of the buffer unit 4 isconstant in these control methods, the amount of mono-silane gas to beloaded can be precisely controlled by accurately measuring thetemperature and pressure of the buffer unit 4 in which the mono-silanegas is to be used in an optimum state. In such a case, no flow rate ofthe mono-silane gas is required to be measured. The semiconductormanufacturing device 1 or the semiconductor manufacturing system canadopt any of or any combination of the first to third control methods inorder to obtain products (e.g. semiconductor devices) which satisfyrequired specifications, have reasonable cost and so on.

[0069] In the semiconductor manufacturing device 1 or the semiconductormanufacturing system including the buffer unit 4, the mono-silane gas isquickly supplied to and stored in the buffer unit 4 regardless of anactual period for forming the polycrystalline silicon film. It ispossible to shorten the time period during which the semiconductormanufacturing device 1 is in connection with the external source 20.Further, the buffer unit 4 stores the mono-silane gas before the filmforming process is started in the substrate treating chamber 2, so thatit is possible to remarkably reduce a chance in which the film formingprocess is interrupted due to an accident or malfunction of thesemiconductor manufacturing system (in the semiconductor manufacturingplant), interruption or reduction of the mono silane gas due toman-caused errors, and so on. This means that the polycrystallinesilicon films can be more reliably and efficiently formed.

[0070] Further, the mono-silane gas can be delivered to and stored inthe buffer unit 4 longer than the film depositing period. This iseffective in downsizing the facilities for supplying and delivering themono-silane gas, (e.g. delivery pipes may be made thin), and inextensively reducing the cost of the foregoing facilities. The necessarycost can be drastically decreased for supply and delivery.

[0071] (4) While the mono-silane gas is being filled and stored in thebuffer unit 4, semiconductor wafers are conveyed into the substratetreating chamber 2 which has been evacuated for the purpose of filmdeposition. The substrate treating chamber 2 has its temperatureadjusted to 620° C. by the heater 202, and the pressure thereof adjustedto 26.6 Pa by the vacuum exhaust pump 30.

[0072] Referring to FIG. 5, the mass flow controller 811 is providedbetween the pneumatic valve 801 and the substrate treating chamber 2,i.e. behind the buffer unit 4, thereby regulating a feed rate of themono-silane gas to the substrate treating chamber 2 from the buffer unit4.

[0073] When the conductance regulator 812 is positioned behind thebuffer unit 4 (as shown in FIG. 6) and is used together with thepneumatic valve 801, the feed rate of the mono-silane gas can beregulated without using the mass flow controller 811. The conductanceregulator 812 may be preferably an orifice, a piezzo valve or the like.The conductance regulator 812 regulates the feed rate of the mono-silanegas such that the mono-silane gas is reduced at the rate of 1×10⁴ Pa/minwhere the output of the measuring unit 5 (e.g. a pressure value)uniformly decreases. This is because the mono-silane gas having thepressure of 1×10⁵ Pa is completely consumed for 10 minutes.

[0074] Therefore, it is not necessary to precisely measure the 1000 sccmono-silane gas used for the film deposition prior to the manufacturingprocess.

[0075] (5) A polycrystalline silicon film is formed under the conditionsof 100 sccm and 10 minutes. After the film deposition, the mono-silanegas remaining in the buffer unit 4 is directly discharged to the vacuumexhaust pump 30 via a bi-path line 804 which is opened or closed by avalve 803 but without via the substrate treating chamber 2. Otherwise,the mono-silane gas in the buffer unit 4 is stored for the nextfollowing film deposition.

[0076] (6) The mono-silane gas and so on discharged by the vacuumexhaust pump 30 are purified by the purifier 31, and are sent to anexhaust duct 32.

[0077] After the foregoing LPCVD process, the polycrystalline siliconfilm is completed on the semiconductor wafer.

[0078] [Application to Batch Processing]

[0079] The invention is applicable to a batch processing in which 100 to200 semiconductor wafers, for instance, are placed in the substratetreating chamber 2 and on which polycrystalline silicon films are formedusing the semiconductor manufacturing device 1 (LPCVD device).

[0080] In the batch processing, semiconductor wafers are verticallyplaced, with 5 mm spaces kept therebetween, in a vertical substratetreating chamber 2 (a vertical LPCVD furnace) of the semiconductormanufacturing device 1. The substrate treating chamber 2 is heated to areaction temperature of 620° C., for example, and becomes stable. Themono-silane gas whose feed rate has been controlled by the mass flowcontroller or the like is supplied to the substrate treating chamber 2.However, the mono silane gas is consumed at an upper part of thesubstrate treating chamber 2, and a reaction gas is generated, so thatthe mono-silane gas may be diluted at a lower part of the substratetreating chamber 2. This means that film deposition will be slowed down.Specifically, the mono-silane gas is consumed by the deposition or vaporreaction as expressed by the following reaction formula, and silylenegas (SiH₂) or a hydrogen gas (H₂) is generated. As a result, a partialpressure of the mono-silane gas (SiH₄) is reduced, so that thedeposition speed is reduced.

[0081] SiH₄→SiH₂+H₂ (vapor reaction)

[0082] SiH₄→Si+2H₂ (deposition reaction)

[0083] SiH₂→Si+H₂ (deposition reaction)

[0084] When the mono-silane gas is continuously supplied to thesubstrate treating chamber 2 at the predetermined feed rate, e.g. 100sccm, film deposition on semiconductor wafers at the lower part of thesubstrate treating chamber 2 will be slowed down for the foregoingreasons. The vertical spaces between the semiconductor wafers are small,i.e. 5 mm, compared with a diameter thereof. The mono-silane gas isdiffused toward the centers of the semiconductor wafers via peripheralareas thereof. In each semiconductor wafer, the peripheral area is anupstream while the center is a downstream. Therefore, thepolycrystalline silicon film is quickly formed at the upstream comparedwith at the downstream, and is thin at the downstream.

[0085] In the first embodiment, the feed rate of the mono-silane gas tothe buffer unit 4 is controlled by the mass flow controller 811 (shownin FIG. 5) or by the conductance regulator 812 (shown in FIG. 6), whichenables the polycrystalline silicon films to be uniformly deposited.Further, the amount of the mono-silane gas used for the film depositioncan be controlled on the basis of a total amount thereof supplied to thesubstrate treating chamber 2 from the buffer unit 4, so that thepolycrystalline silicon films will have the uniform thickness. In thiscase, the feed rate of the mono-silane gas is not controlled at all asshown in FIG. 7.

[0086]FIG. 8 is the flow chart showing the sequence of the LPCVD processfor which the gas source of FIG. 7 is utilized.

[0087] (1) First of all, the mono-silane gas is delivered to the bufferunit 4 from the mono-silane gas cylinder 21 of the external source 20.The buffer unit 4 temporarily stores the mono-silane gas (step S80). Theamount of the mono-silane gas is measured in order that the buffer unit4 stores a predetermined amount thereof.

[0088] The presence of the buffer unit 4 is effective in reducing adifference between the time when the mono-silane gas is required and thetime to supply the gas. This is effective in preventing the gas sourcefrom having an excessively large capacity, and in reducing costs of thegas source and delivering facilities. Further, the mono-silane gas iscontrolled on the basis of the total amount thereof in place of the feedrate thereof, which is effective in promoting quick supply of themono-silane gas, in controlling the vaporization of solids or liquids,and in enabling supply of intermediate precursors and so on in responsethe chemical reaction.

[0089] (2) The gate valve 802 is opened in order to sufficientlyevacuate the substrate treating chamber 2 using the vacuum exhaust pump30 (step S81).

[0090] (3) When the pressure of the substrate treating chamber 2 islowered to 0.133 Pa, for example, the gate valve 802 is completelyclosed, thereby sealing the substrate treating chamber 2 (step S82).

[0091] (4) The pneumatic valve 801 between the substrate treatingchamber 2 and the buffer unit 4 is fully opened, thereby filling thesubstrate treating chamber 2 with the target amount of the mono-silanegas in several seconds (step S83). Therefore, the mono-silane gas can bequickly filled in and diffused throughout the narrow spaces between thesemiconductor wafers in the substrate treating chamber 2 compared withthe reaction speed thereof. In other words, it is possible to reducechances in which deposited films are non-uniform due to adiffusion-limit of the mono-silane gas. As a result, the polycrystallinesilicon films can have a uniform thickness.

[0092] When the external source of FIG. 7 is used, the concentration ofthe mono-silane gas reduces as polycrystalline silicon films are beingdeposited as shown in FIG. 9. Further, a film deposition rate varieswith the time as shown in FIG. 10. These differ from the case where thesupply amount of the mono-silane gas is controlled by the mass flowcontroller or the like. However, the target film thickness is derived byintegrating the film deposition data, so that the film deposition periodcan be determined on the target film thickness. Referring to FIG. 10,the film deposition rate is large immediately after the start of thefilm deposition, becomes smaller with the lapse of time, and graduallyis stabilized as the target thickness is attained. Therefore, thepolycrystalline silicon films can be formed as reliably and quickly aspossible, and have the uniform thickness.

[0093] (5) The film deposition is carried out until the target thicknessis accomplished (step S84).

[0094] (6) The gate valve 802 is fully opened after the deposited filmshave the target thickness, so that non-used mono-silane gas and so onare discharged from the substrate treating chamber 2 by the vacuumexhaust pump 30. In this state, the film deposition will be completed(step S85).

[0095] [Application to Deposition of Doped Silicon Film]

[0096] The foregoing semiconductor manufacturing device 1 orsemiconductor manufacturing system is also applicable to the depositionof polycrystalline (or single crystal) silicon films which are dopedwith impurities such as arsenic (As), boron (B), phosphor (P),impurities such as germanium (Ge) of the IV group element similarly tosilicon or the like. These impurities are used as donors or acceptors,and are doped into films being deposited.

[0097] The semiconductor manufacturing device 1 or semiconductormanufacturing system also includes another buffer unit (which is similarto the buffer unit 4 for the mono-silane gas, but is not shown) in orderto store impurities and to obtain doped polycrystalline silicon films.This buffer unit stores source gases such as an arsine gas (AsH₃), adiborane gas (B₂H₆), a phosphine gas (PH₃), a germane gas (GeH₄) or thelike which are used as dopants. The source gases are supplied to thesubstrate treating chamber 2 similarly to the mono-silane gas, therebyeasily obtaining doped polycrystalline silicon films.

[0098] Alternatively, both the mono-silane gas and the foregoing sourcegases (e.g. arsine gas and so on) may be mixed and stored together inthe buffer unit 4. The dopants can be controlled in order to have auniform concentration before they are delivered to the buffer unit 4.

[0099] In the foregoing case, the measuring unit 5 is further providedwith a mass spectrograph, an infrared absorption spectrograph and so on,analyzes the gases stored in the buffer unit 4, and outputs analyzedresults to the CIM system. Therefore, it is possible to precisely detectconcentrations of the mixed gases prior to the film deposition. Further,the concentration and amount of the mono-silane gas and source gases tothe buffer unit 4 can be easily controlled by operating the pneumaticvalve 702 and so on which control the feed rates of the gases.

[0100] Still further, even when the measuring unit 5 includes only apressure gauge, mixing ratios of the mono-silane gas and source gasescan be easily calculated by measuring pressure increases thereof usingthe pressure gauge when these gases are stored in the buffer unit 4.

[0101] Both non-doped and doped polycrystalline silicon films are madein the identical manner regardless of the methods for storing the mixedgases in the buffer unit 4.

[0102] [Application to Making Insulating Film: Liquid Source]

[0103] The semiconductor manufacturing device 1 or the semiconductormanufacturing system is still further applicable to making insulatingfilms. The following describe how a tantalum oxide film is made usingthe LPCVD process.

[0104] Referring to FIG. 11, the external source 20 is provided with aliquid tank 25 where penta ethoxyl tantalum (called the “PET”) isstored. The PET is a liquid at normal pressures and normal temperatures.An amount of the PET necessary for the substrate treatment is measuredand controlled at least by a weight meter 251, a liquid level gauge 252,a liquid scale 253, or the mass flow controller (MFC) 254. The PET isdelivered to the buffer unit 4.

[0105] The buffer unit 4 further includes a heater and a thermostat 40.The PET delivered to the buffer unit 4 is heated by the heater under thecontrol of the thermostat 40, is vaporized in a state where it does notthermally react, is changed to a gas, and is stored in the buffer unit4.

[0106] The PET is delivered to the substrate treating chamber 2 from thebuffer unit 4, and is used to obtain the tantalum oxide film using theLPCVD process. Since the semiconductor manufacturing device 1 or thesemiconductor manufacturing system includes the buffer unit 4, thesubstrate treating substance can be reliably supplied without anyproblem caused by a reduced capacity of a vaporizer or the like inresponse to the vapor phase LPCVD reaction of the PET which is liquid atthe normal pressures and temperatures. Further, the necessary amount ofsource gases can be reliably supplied for forming tantalum oxide films.

[0107] [Application to Making Metal Film: Solid and Liquid Sources]

[0108] The semiconductor manufacturing device 1 or the semiconductormanufacturing system is also applicable to forming metal films (e.g.platinum films). The following describe how ruthenium films are made bythe LPCVD process.

[0109] Referring to FIG. 12, the external source 20 includes a solidtank 26 storing ruthenium cyclopentane (Ru(Cp)2) powders, grains orpellets at the normal pressures and temperatures. A necessary amount ofthe ruthenium cyclopentane is supplied to the buffer unit 4. For thispurpose, at least a weight and weighing capacity of rutheniumcyclopentane are measured by a weightometer 261 and a weighing scale263, respectively , or the number of powders, grains or pellets thereofis counted by a counter 264.

[0110] The buffer unit 4 includes a heater and a thermostat 40 which aresimilar to those shown in FIG. 11. The ruthenium cyclopentane isvaporized by the heater and thermostat 40 in the buffer unit 4, and isstored therein.

[0111] The stored ruthenium cyclopentane is delivered to the substratetreating chamber 2, so that a ruthenium film can be formed by the LPCVDprocess similarly to the polycrystalline silicon film using themono-silane gas.

[0112] The semiconductor manufacturing device 1 or the semiconductormanufacturing system includes the buffer unit 4, so that the solidsubstrate treating substance (Ru(Cp)2) can be reliably supplied withoutany problem caused by a reduced capacity of a vaporizer or the like inresponse to the vapor phase LPCVD reaction. Further, the necessaryamount of source gases can be reliably supplied in order to fromruthenium cyclopentane films.

[0113] Further, ruthenium ethyl cyclopentane (Ru(EtCP)2) which is liquidat the normal pressures and temperatures can be used for formingruthenium films. In this case, the semiconductor manufacturing device 1or the semiconductor manufacturing system of FIG. 11 is also usable.

[0114] (Second Embodiment of the Invention)

[0115] In this embodiment, the buffer unit 4 of the first embodiment isprovided as an external semiconductor manufacturing device.

[0116] Referring to FIG. 13, the external semiconductor manufacturingdevice 1A is provided as an external device in addition to thesemiconductor manufacturing device 1 with the substrate treating chamber2, and includes the buffer unit 4 in order to receive and store thesubstrate treating substance from the external source 20, and deliversthe stored substrate treating substance to the substrate treatingchamber 2 of the semiconductor manufacturing device 1.

[0117] The external semiconductor manufacturing device 1A includes: acontrol unit 6A controlling the substrate treating substance in thebuffer unit 4; the measuring unit 5 measuring the substrate treatingsubstance; the pneumatic valve 702 controlling the delivery of themono-silane gas from the mono-silane gas cylinder 21 of the externalsource 20; the pneumatic valve 703 controlling the delivery of thenitride gas from the nitride gas generator 22; the pneumatic valve 701controlling the delivery of the fluorine gas from the fluorine gasgenerator 23; and the pneumatic valve 801 controlling the delivery ofthe substrate treating substance to the substrate treating chamber 2 ofthe semiconductor manufacturing device 1 from the buffer unit 4. Thecontrol unit 6A is dedicated to the buffer unit 4, controls thepneumatic valves 701 to 703 and 801, and is controlled by the CIM systemvia the LAN 13.

[0118] In this embodiment, the semiconductor manufacturing device 1 isessentially identical to the semiconductor manufacturing device 1 of thefirst embodiment except for the buffer unit 4, measuring unit 5,pneumatic valves 701 to 703 and 801, all of which constitute theexternal semiconductor manufacturing device 1A. The externalsemiconductor manufacturing device 1A includes the control unit 6Adedicated to the buffer unit 4 in order to control the temperatures ofthe heater 202 and the operation of the gate valve 802.

[0119] The external semiconductor manufacturing device 1A including thebuffer unit 4 functions as an external unit for the semiconductormanufacturing device 1 which actually deposits films. The combination ofthe semiconductor manufacturing devices 1 and 1A is as effective as thesemiconductor manufacturing device 1 or the semiconductor manufacturingsystem of the first embodiment. Further, the external semiconductormanufacturing device 1A is very versatile, and can be attached to adifferent semiconductor manufacturing device, e.g. a sputtering device,an etching device, a cleaning device or the like.

[0120] (Third Embodiment of the Invention)

[0121] In this embodiment, the semiconductor manufacturing device 1 orthe semiconductor manufacturing system of the first embodiment isapplied to cleaning an inner wall of a reaction tube 201 of thesubstrate treating chamber 2.

[0122] [Basic Cleaning Method]

[0123] The following describe, with reference to FIG. 1, how to cleanthe inner wall of the reaction tube 201 covered with polycrystallinesilicon films deposited by the LPCVD process. The foregoing processdirectly relates to the making of the polycrystalline silicon films.However, the cleaning process is indirect but indispensable to make thepolycrystalline silicon films.

[0124] (1) First of all, cleaning data are transmitted to the controlunit 6 of the semiconductor manufacturing device 1 from the manufacturemanaging database 11 via the LAN 13 as shown in FIG. 1. The cleaningdata denote at least etching data and so on which are necessary toremove the polycrystalline silicon films from the inner wall of thesubstrate treating chamber 2. For instance, in order to remove a 100nm-thick polycrystalline silicon film from the inner wall of thereaction tube 201, etching should be performed by introducing for 5minutes a fluorine gas at the feed rate of 1000 sccm, at the temperatureof 300° C. and at the pressure of 1.333×10³ Pa. A total of 5000 sccfluorine gas will be introduced in 5 minutes.

[0125] (2) In this embodiment, the buffer unit 4 has a capacity of 5000scc in order to clean the substrate treating chamber 2. In response tothe cleaning data, the control unit 6 opens the pneumatic valve 801,thereby evacuating the buffer unit 4 to a sufficiently low pressure bythe vacuum exhaust pump 30.

[0126] (3) Thereafter, the control unit 6 closes the pneumatic valve801, and opens the pneumatic valve 701, so that the fluorine gas will beintroduced into the buffer unit 4 from the fluorine gas generator 23 ofthe external source 20.

[0127] (4) The 5000 scc fluorine gas (corresponding to 5000 cm³ of thefluorine gas in the normal state) is filled in the buffer unit 4, and isstored therein as soon as the control unit 6 closes the pneumatic valve701. The fluorine gas generator 23 generates the fluorine gas by theelectrolysis of KF and 2HF, or pyrolysis of KF and 6HF. When thefluorine gas is generated at the rate of 100 sscm/min, the fluorine gasgenerator 23 should have a capacity which is ten times as large as itsnormal capacity in order to generate the fluorine gas at the feed rateof 1000 sccm. However, such a feed rate is necessary for onlyapproximately 5 minutes for the cleaning process.

[0128] In this embodiment, the buffer unit 4 starts to store thefluorine gas 50 minutes prior to the cleaning process, so that thenecessary 1000 sccm fluorine gas can be obtained even when the fluorinegas generator 23 has only the 100 sccm capacity.

[0129] In other words, the buffer unit 4 starts storing the fluorine gasimmediately after the polycrystalline silicon film is formed and themono silane gas is emitted therefrom. Further, the fluorine gas isstored during the cleaning of the reaction tube 201, during the returnof the pressure in the buffer unit 4 to the normal state, during theunloading of the semiconductor wafer from the substrate treating chamber2, and during the evacuation and thermal stabilization of the bufferunit 4 for the cleaning process. Therefore, the cleaning period is notlengthened.

[0130] Alternatively, the buffer unit 4 is dedicated to the storage ofthe mono-silane gas, and a cleaning buffer unit 4 may be provided inorder to store the fluorine gas. The cleaning buffer unit 4 may beincorporated in the semiconductor manufacturing device 1 as in the firstembodiment, or may be provided as an external unit similarly to theexternal semiconductor manufacturing device 1A of the second embodiment.

[0131] (5) The fluorine gas is delivered to the substrate treatingchamber 2 from the buffer unit 4 in order to clear the substratetreating chamber 2.

[0132] Generally speaking, the substrate treating chamber 2 is cleanedless frequently than the number of times of polycrystalline silicon filmdeposition, which is effective in reducing the supply capacity of thefluorine gas generator 23. In other words, capacities of the externalsource 20 and gas delivery facilities can be reduced, and capitalinvestment for such an external source and gas delivery facilities canbe also reduced.

[0133] In the third embodiment, the cleaning process (etching process)for the substrate treating chamber 2 is essentially identical to thepolycrystalline silicon film deposition in the first embodiment.Especially, in the cleaning process, a final point of temperature rise,analysis of exhaust gases and so on in the reaction tube 20 can bemonitored on the real time basis. Therefore, the semiconductormanufacturing system shown in FIG. 7 is very effective since it controlsthe cleaning process on the basis of a total amount of supplied fluorinegas without controlling the feed rate of the fluorine gas using the massflow controller 811, conductance regulator 812 and so on. In thesemiconductor manufacturing system of FIG. 7, it is not necessary tomeasure time-dependent variations of the etching rate beforehand.

FIRST MODIFIED EXAMPLE

[0134] In a first modified example of the third embodiment, thesemiconductor manufacturing device 1 or the semiconductor manufacturingsystem includes a retrieving buffer unit 35 (a second buffer unit)between the substrate treating chamber 2 and the vacuum exhaust pump 30in parallel. Referring to FIG. 14, the retrieving buffer unit 35connects to the external source 20 via a three-way valve 805, to thevacuum exhaust pump 30 via a valve 806, and to the buffer unit 4 via areturn valve 807.

[0135] The retrieving buffer unit 35 retrieves and stores the cleaninggas (fluorine gas) exhausted from the substrate treating chamber 2, anddelivers it to the buffer unit 4. The fluorine gas returned to thebuffer unit 4 is reused for a next following cleaning of the substratetreating chamber 2, which is effective in promoting to effective use ofthe cleaning gas, reducing cleaning cost, and promoting energy saving.The retrieving buffer unit 35 may be positioned in either in or out ofthe semiconductor manufacturing device 1.

SECOND MODIFIED EXAMPLE

[0136] Referring to FIG. 15, the semiconductor manufacturing systemincludes a temporary storage buffer unit 36 between the vacuum exhaustpump 30 and the purifier 31. The temporary storage buffer unit 36temporarily stores an exhaust gas, and is connected to the vacuumexhaust pump 30 via a three-way valve 808 and an exhaust gas compressor37, to the nitride gas generator 22 via a valve 810 in order to supply anitride gas, and to the purifier 31 via a return valve 809.

[0137] In this modified example, the semiconductor manufacturing device1 handles not only the substrate treating substances such as sourcegases used for the film deposition and cleaning gases used for thecleaning of the substrate treating chamber 2, and it also handles theexhaust gas. Specifically, the temporary storage buffer unit 36 isprovided in a path for discharging exhaust gases, and functionssimilarly to the buffer unit 4. If exhaust gases are discharged beyondthe capacity of the purifier 31, the temporary storage buffer unit 36controls a feed rate of the exhaust gases. Generally, the purifier 31operates only while the exhaust gases are being discharged. Thetemporary storage buffer unit 36 enables the purifier 31 to processexhaust gases from a plurality of semiconductor manufacturing devices 1(not shown).

[0138] In the foregoing case, the temporary storage buffer unit 36temporarily stores exhaust gases, and gradually supplies them to thepurifier 31, so that the purifier 31 can reliably process them. Even ifone semiconductor manufacturing device 1 happens to discharge exhaustgases beyond the capacity of the purifier 31, the temporary storagebuffer unit 35 operates as described above.

[0139] Therefore, the purifier 31 can have a reduced capacity. Further,a setting number of purifiers 31 can be reduced in the semiconductormanufacturing system. The gas source and delivery facilities of thesemiconductor manufacturing system can be downsized, and capitalinvestment for such facilities can be reduced.

[0140] (Fourth Embodiment of the Invention)

[0141] In this embodiment, the present invention is applied to thecleaning of inner walls of reaction tubes in the substrate treatingchambers of a plurality of semiconductor manufacturing devices in thesemiconductor manufacturing system of the third embodiment.

[0142] [Basic Structure of Semiconductor Manufacturing Device andSemiconductor Manufacturing System]

[0143] Referring to FIG. 16, the semiconductor manufacturing systemcomprises at least: a plurality of semiconductor manufacturing devices1(1), 1(2) and 1(3); an external source 20 supplying substrate treatingsubstances to the semiconductor manufacturing devices 1(1) to 1(3); aexternal semiconductor manufacturing device 1B distributing thesubstrate treating substances to the semiconductor manufacturing devices1(1) to 1(3); and a CIM server 14.

[0144] The semiconductor manufacturing device 1(1) is essentiallyidentical to the semiconductor manufacturing device 1 of the firstembodiment (refer to FIG. 1), and includes at least: a substratetreating chamber 2; a buffer unit 4 receiving and storing the substratetreating substances from the external source 20 and delivering thesubstrate treating substances to the substrate treating chamber 2 or thesemiconductor manufacturing device 1(1); a control unit 6(1) controllingthe states of the substrate treating substances in the buffer unit 4(1);and a measuring unit 5 (not shown) measuring the state of the substratetreating substances. The control unit 6(1) is connected to the CIMserver 14 via the LAN 13.

[0145] The semiconductor manufacturing device 1(2) is identical to thesemiconductor manufacturing device 1(1), and includes at least: asubstrate treating chamber 2 (not shown), a measuring unit 5, a bufferunit 4(2), and a control unit 6(2). The semiconductor manufacturingdevice 1(3) includes at least: a substrate treating chamber 2 (notshown), a measuring unit 5, a buffer unit 4(3), and a control unit 6(3).The semiconductor manufacturing system is assumed to include threesemiconductor manufacturing devices 1(1) to 1(3) in order to simplifythe description thereof. Alternatively, the semiconductor manufacturingsystem may have two semiconductor manufacturing devices 1 or four ormore semiconductor manufacturing devices 1.

[0146] The external semiconductor manufacturing device 1B is essentiallyidentical to the external semiconductor manufacturing device 1A of thesecond embodiment (shown in FIG. 13), but does not include a substratetreating chamber 2, and functions only as a buffer. Specifically, theexternal semiconductor manufacturing device 1B receives and stores thesubstrate treating substances from the external source 20, and includesa buffer unit 4B delivering the substrate treating substances to anexternal unit, distribution valves 721, 722 and 723, and a control unit6B controlling the operations of the valves 721 to 723.

[0147] In this embodiment, the substrate treating chambers 2 of thesemiconductor manufacturing devices 1(1) to 1(3) are cleaned usingfluorine gases temporarily stored in the buffer unit 4B, which isconnected to a fluorine gas generator 23 of the external source 20.

[0148] The distribution valve 721 is positioned between the buffer unit4B and the semiconductor manufacturing device 1(1), and is controlled bythe control unit 6B. The distribution valve 722 is provided between thebuffer unit 4B and the semiconductor manufacturing device 1(2), and iscontrolled by the control unit 6B. The distribution valve 723 isprovided between the buffer unit 4B and the semiconductor manufacturingdevice 1(3), and is controlled by the control unit 6B. The control unit6B is connected to the CIM server 14 via the LAN 13.

[0149] The CIM server 14 stores information concerning order ofprocessing raw semiconductor wafer lots, information concerning kinds oflots, and classified information concerning priorities of processingsequences in manufacturing lines, and so on. The CIM server 14 managesmanufacturing schedules on the basis of these pieces of information,i.e. which lot should be processed and when it should be processed bythe semiconductor manufacturing device 1(1), 1(2) or 1(3).

[0150] The CIM server 14 can calculate currently accumulated thicknessesof the polycrystalline silicon films obtained in each substrate treatingchamber 2 of each of the semiconductor manufacturing devices 1(1) to1(3). Further, the CIM server 14 can artificially or automaticallycalculate and estimate a recommended film thickness for cleaning thesubstrate treating chambers 2 on the basis of chronological information,in present or past, on film thicknesses or film dust. Still further, theCIM server 14 can prepare schedules concerning a time to clean thesubstrate treating chambers 2 on the basis of the calculated andestimated data, information concerning current or waiting lots,manufacture schedules and so on.

[0151] [Operation of Semiconductor Manufacturing Device andSemiconductor Manufacturing System, and Substrate Treating Method]

[0152] The cleaning is performed as briefly described hereinafter.

[0153] (1) First of all, the CIM server 14 prepares a cleaning schedulefor the semiconductor manufacturing device 1(1), 1(2) or 1(3) whichshould be cleaned. It is assumed here that the substrate treatingchamber 2 of the semiconductor manufacturing device 1(1) should becleaned first.

[0154] (2) In accordance with the cleaning schedule, the CIM server 14not only provides control information to the control unit 6(1) of thesemiconductor manufacturing device 1(1) via the LAN 13 and opens thepneumatic valve 701, but also provides the control information to thecontrol units 6(2) and 6(3) of the semiconductor manufacturing devices1(2) and 1(3), and closes the pneumatic valves 701 of the semiconductormanufacturing devices 1(2) and 1(3).

[0155] (3) The fluorine gas generator 23 supplies the fluorine gas tothe buffer unit 4B of the external semiconductor manufacturing device1B. The buffer unit 4B stores the fluorine gas therein.

[0156] (4) The CIM server 14 opens the distribution valve 721 via thecontrol unit 6B of the external semiconductor manufacturing device 1B,and closes the distribution valves 722 and 723. The fluorine gas fromthe buffer unit 4B is delivered to and stored in the buffer unit 4(1) ofthe semiconductor manufacturing device 1(1). An amount of the fluorinegas in the buffer unit 4(1) is equal to the amount necessary for thecleaning process which has been calculated by the CIM server 14 on thebasis of the accumulated film thickness information. For instance, theamount of the stored fluorine gas can be easily measured and controlledusing the pressure regulator 710 (shown in FIG. 2), the mass flowcontroller 711 (shown in FIG. 3) or the conductance regulator 712 (shownin FIG. 4). When the preset amount of the fluorine gas is stored in thebuffer unit 4(1), this information is transmitted to the CIM server 14via the LAN 13.

[0157] (5) The CIM server 14 starts to supply the fluorine gas to thebuffer units 4(2) and 4(3) of the semiconductor manufacturing device1(2) and 1(3), respectively, in accordance with the priority of the nextfollowing cleaning process. These buffer units 4(2) and 4(3) can storethe fluorine gas necessary for the cleaning process.

[0158] (6) In the foregoing state, if the fluorine gas stored in thebuffer units 4(1) to 4(3) is not in use, the fluorine gas supplied fromthe fluorine gas generator 23 is stored in the buffer unit 4B of theexternal semiconductor manufacturing device 1B to a pressure limit.Further, when the fluorine gas in the buffer units 4(1) to 4(3) is notstill in use, the fluorine gas generator 23 is stopped in response to acontrol command from the CIM server 14.

[0159] (7) The substrate treating chamber 2 of the semiconductormanufacturing device 1(1) is cleaned using the fluorine gas in thebuffer unit 4(1). Further, the substrate treating chambers 2 of thesemiconductor manufacturing devices 1(2) and 1(3) are also cleaned usingthe fluorine gases in the buffer units 4(2) and 4(3), respectively.

[0160] In the fourth embodiment, the external semiconductormanufacturing device 1B including the buffer unit 4B serves for thedevices 4(1) to 4(3), which enables effective use of the fluorine gasgenerator 23. Therefore, it is possible to downsize the fluorine gasgenerator 23 and facilities for supplying the fluorine gas, and reduceinstallation cost, maintenance cost and so on.

[0161] Further, the external semiconductor manufacturing device 1B withthe buffer unit 4B serves for semiconductor manufacturing deviceswithout any buffer units in addition to the semiconductor manufacturingdevices 4(1) to 4(3). For instance, those semiconductor manufacturingdevices can be designed in a manner such that any of their valves canoperate together with the valve 721, 722 or 723 of the externalsemiconductor manufacturing device 1B in response to the control commandfrom the CIM server 14. In this case, those semiconductor manufacturingdevices can function as if they include buffer units 4.

[0162] The external semiconductor manufacturing device 1B with thebuffer unit 4B is attached as an external unit to the external source 20in the fourth embodiment. Alternatively, the external semiconductormanufacturing device 1B may be incorporated in the external source 20.

MODIFIED EXAMPLE

[0163] In a modified example of the fourth embodiment, a semiconductormanufacturing system comprises at least the semiconductor manufacturingdevices 1(1), 1(2) and 1(3), the external source 20 supplying thesubstrate treating substances to the semiconductor manufacturing devices1(1) to 1(3), a external semiconductor manufacturing device ICdistributing the substrate treating substances from the external source20 to the semiconductor manufacturing devices 1(1) to 1(3), and the CIMserver 14 managing the semiconductor manufacturing devices 1(1) to 1(3).Refer to FIG. 17.

[0164] The semiconductor manufacturing device 1(1) is essentiallyidentical to the semiconductor manufacturing device 1 of the secondembodiment (shown in FIG. 13), and includes at least a substratetreating chamber 2, and a control unit 6(1) controlling the substratetreating chamber 2. The control unit 6(1) is connected to the CIM server14 via the LAN 13. However, the semiconductor manufacturing device 1(1)does not include any buffer unit 4(1), and differs from thesemiconductor manufacturing device 1(1) of the fourth embodiment in thisrespect.

[0165] The semiconductor manufacturing devices 1(2) and 1(3) include atleast treating chambers 2 and control units 6(2) and 6(3), respectively.The following describe the semiconductor manufacturing system havingthree semiconductor manufacturing devices 1(1) to 1(3). Alternatively,the semiconductor manufacturing system may have two or more than foursemiconductor manufacturing devices.

[0166] The external semiconductor manufacturing device IC is essentiallyidentical to the external semiconductor manufacturing device 1B of thefourth embodiment (shown in FIG. 16), but does not have any substratetreating chamber 2, and functions as a dedicated buffer unit. Theexternal semiconductor manufacturing device IC includes at least a mainbuffer unit 4C and sub-buffer units 4C1 to 4C3. The main buffer unit 4Creceives the substrate treating substance from the external source 20,stores them and delivers them to the sub-buffer units 4C1 to 4C3, whichtransfer them to the semiconductor manufacturing devices 1(1) to 1(3).

[0167] The external semiconductor manufacturing device IC includes:valves 721 to 723 via which the substrate treating substance isdistributed to the sub-buffer units 4C1 to 4C3 from the main buffer unit4C; pneumatic valves 725 to 727 via which the substrate treatingsubstance is distributed to the semiconductor manufacturing devices 1(1)to 1(3); and a control unit 6C controlling the operations of the valves721 to 723 and 725 to 727, and is connected to the CIM server 14 via theLAN 13.

[0168] The substrate treating substance, i.e. the fluorine gas, in themain buffer unit 4C is used for cleaning the substrate treating chambers2 of the semiconductor manufacturing devices 1(1) to 1(3). Specifically,the fluorine gas from the fluorine gas generator 23 is temporarilystored in the main buffer unit 4C, is distributed to the sub-bufferunits 4C1 to 4C3, and is temporarily stored therein. Thereafter, thefluorine gas is delivered to the semiconductor manufacturing devices1(1) to 1(3) via the pneumatic valves 725 to 727. In short, the externalsemiconductor manufacturing device IC includes the sub-buffer units 4C1to 4C3 which serve for the semiconductor manufacturing devices 1(1) to1(3).

[0169] The semiconductor manufacturing system of the modified example isas effective and advantageous as the semiconductor manufacturing systemof the fourth embodiment.

[0170] In the modified example, the external semiconductor manufacturingdevice IC is provided as an external unit for the external source 20.Alternatively the external semiconductor manufacturing device 1C may beincorporated in the external source 20.

[0171] (Fifth Embodiment of the Invention)

[0172] In this embodiment, the present invention is applied to asemiconductor wafer cleaning device (semiconductor manufacturing device)and a semiconductor wafer cleaning system (semiconductor manufacturingsystem) in which a cleaning agent can be recycled.

[0173] [Basic Structure of Semiconductor Manufacturing Device andSemiconductor Manufacturing System]

[0174] Referring to FIG. 18, the semiconductor manufacturing system(semiconductor wafer cleaning system) comprises at least: semiconductormanufacturing devices 1(4), 1(5) and 1(6) cleaning substrates; a primarytube 90 introducing a cleaning agent; an evaporating/refining unit 95which evaporates and refines the cleaning agent discharged from thesemiconductor manufacturing devices 1(4), 1(5) and 1(6); and externalsemiconductor manufacturing devices ID, 1E and 1F which are providedwith buffer units 4D, 4E and 4F receiving and storing the cleaning agentfrom the primary tube 90 or the evaporating/refining unit 95,respectively.

[0175] Although not shown in detail, the semiconductor manufacturingdevice 1(4) is structured to function as a single wafer cleaning device.In other words, the semiconductor manufacturing device 1(4) is sheet-fedprocessing type cleaning device. The semiconductor manufacturing devices1(5) and 1(6) whose structure is not shown in detail function assemiconductor wafer cleaning devices of the batch processing type.

[0176] A primary tube 90 is arranged in the clean room 100, andsimultaneously supplies the cleaning agent, i.e. a hydrogen fluoridesolution (HF), to the semiconductor manufacturing devices 1(4) to 1(6)via control valves 731, which are opened or closed by the database 11 ofthe CIM system via the LAN 13.

[0177] The hydrogen fluoride solution used for cleaning semiconductorwafers is discharged from the semiconductor manufacturing devices 1(4)to 1(6) to the evaporating/refining unit 95 via a conduit pipe 91.Specifically, a part of the hydrogen fluoride solution is used forcleaning semiconductor wafers (i.e. for etching silicon oxide films)while a part of the remaining hydrogen fluoride solution is diluted bypure water or like, and is discharged via the conduit pipe 91. Only thehydrogen fluoride components of the discharged hydrogen fluoridesolution are extracted and refined by the evaporating/refining unit 95.The refined hydrogen fluoride solution is delivered to the externalsemiconductor manufacturing devices 1D to 1F via a return pipe 94, andis reused. Non-reused hydrogen fluoride solution is discharged via anindustry effluent pipe 93.

[0178] The buffer unit 4D of the external semiconductor manufacturingdevice 1D stores the hydrogen fluoride solution (supplied via theprimary valve 90 and the control valve 731) and the recycled hydrogenfluoride solution (delivered from the evaporating/refining unit 95 viathe return valve 94 and the control valve 732), and delivers the storedhydrogen fluoride solutions to the semiconductor manufacturing device1(4). The operation of the control valve 732 is controlled by thecontrol unit 6D connected to the CIM system via the LAN 13.

[0179] Similarly to the external semiconductor manufacturing device ID,the buffer unit 4E of the external semiconductor manufacturing device 1Estores the hydrogen fluoride solution (supplied via the primary valve 90and the control valve 731) and the recycled hydrogen fluoride solution(delivered from the evaporating/refining unit 95 via the return valve 94and the control valve 732), and delivers the stored hydrogen fluoridesolutions to the semiconductor manufacturing device 1(5). The operationof the control valve 732 is controlled by the control unit 6E connectedto the CIM system via the LAN 13.

[0180] The buffer unit 4F of the external semiconductor manufacturingdevice IF stores the hydrogen fluoride solution (supplied via theprimary valve 90 and the control valve 731) and the reused hydrogenfluoride solution (delivered from the evaporating/refining unit 95 viathe return valve 94 and the control valve 732), and delivers the storedhydrogen fluoride solutions to the semiconductor manufacturing device1(6). The operation of the control valve 732 is controlled by thecontrol unit 6F.

[0181] [Operation of Semiconductor Manufacturing Device andSemiconductor Manufacturing System, and Substrate Treating Method]

[0182] The following describe the operations of the semiconductormanufacturing devices 1(4) to 1(6) (semiconductor wafer cleaningdevices), external semiconductor manufacturing devices 1D to 1F havingthe buffer units 4D, 4E and 4F, and semiconductor manufacturing system.

[0183] (1) In the semiconductor manufacturing devices 1(4) to 1(6), thehydrogen fluoride solution is delivered to and stored in the bufferunits 4D, 4E and 4F via the primary supply pipe 90 and the control valve731. The hydrogen fluoride solution stored in the buffer units 4D, 4Eand 4F is used for cleaning semiconductor wafers in the semiconductormanufacturing devices 1(4), 1(5) and 1(6), respectively.

[0184] (2) As in the fourth embodiment, the CIM server 14 (not shown)calculates amounts of the hydrogen fluoride solution to be distributedto the semiconductor manufacturing devices 1(4) to 1(6) (not shown) onthe basis of distribution priority order. The operation of the controlvalves 731 and 732 is controlled via the LAN 13 on the basis of thecalculated results. For instance, the hydrogen fluoride solution ispreferentially delivered to the semiconductor manufacturing device 1(4).

[0185] (3) If necessary, an extensively pure hydrogen fluoride solutionfor cleaning semiconductor wafers is preferentially delivered to thesemiconductor manufacturing device 1 via the primary supply pipe 90 andthe buffer unit 4. Otherwise, the recycled hydrogen fluoride solution ispreferentially supplied from the evaporating/refining unit 95.

[0186] (4) Usually, the recycled hydrogen fluoride solution ispreferentially applied to cleaning semiconductor wafers. When therecycled hydrogen fluoride solution becomes short, the hydrogen fluoridesolution is re supplied to the semiconductor manufacturing device 1 viathe primary supply pipe 90 and the buffer unit 4.

[0187] The semiconductor wafer cleaning system of this embodimentincludes the buffer units 4D to 4F in order to store the hydrogenfluoride solution from the primary supply pipe 90 and the recycledhydrogen fluoride solution from the evaporating/refining unit 95. Thehydrogen fluoride solutions are stored in the buffer units 4D to 4Funder control of the CIM system during the cleaning or delivery ofsemiconductor wafers. It is possible to carry out the cleaning processat the predetermined speed, and downsize the semiconductor manufacturingsystem or the cleaning agent delivering facilities. Generally, asemiconductor manufacturing system tends to become bulky when itincludes the recycling unit as well as the evaporating/refining unit 95.As a result, the cleaning agent delivery facilities also become bulky.The semiconductor manufacturing system of the fifth embodiment can bedownsized because it is provided with the buffer units 4D to 4F.

[0188] Alternatively, the semiconductor manufacturing device and thesemiconductor manufacturing system is also applicable to cleaning glasssubstrates, insulating substrates and so on. Further, the externalsemiconductor manufacturing devices 1D to 1F attached to thesemiconductor manufacturing devices 1(4) to 1(6) as external units maybe incorporated therein.

[0189] (Other Embodiments of the Invention)

[0190] The semiconductor manufacturing devices in the first and secondembodiments are LPCVD devices. Alternatively, the present invention isapplicable to CVD devices other than the LPCVD devices (e.g. anatmospheric CVD device or a plasma CVD device), or an epitaxial growthsystem. Further, the present invention is applicable not only to asystem which includes different types of semiconductor manufacturingdevices, film deposition devices, etching units, cleaning units and soon but also other substrate treating methods.

[0191] As described above, the present invention provides thesemiconductor manufacturing device in which only necessary amounts ofsubstances such as gases, liquids and solids directly or indirectly usedfor treating substrates are supplied only when they are necessary, andwhich can downsize the source and delivery pipes.

[0192] Further, the invention provides the semiconductor manufacturingsystem which can downsize substance sources and delivering facilities.

[0193] Finally, the invention provides the substrate treating methodwhich promotes efficient use of the source and delivering facilities.

[0194] Although the present invention has been described and illustratedin detail, it is to be clearly understood that the same is by way ofillustration and example only, and is not to be taken by way oflimitation. The spirit and scope of the present invention are to belimited only by the terms of the appended claims.

What is claimed is:
 1. A semiconductor manufacturing device comprising abuffer unit which receives a substrate treating substance from anexternal source, stores it therein, and delivers it to an external unit.2. A semiconductor manufacturing device comprising: a substrate treatingchamber; and a buffer unit provided in said substrate treating chamberor in said semiconductor manufacturing device, receiving a substratetreating substance from an external source, storing it therein, anddelivering it to said substrate treating chamber or said semiconductormanufacturing device for the purpose of treating substrates.
 3. Thesemiconductor manufacturing device of claim 1 or 2 further comprising acontrol unit controlling states of said substrate treating substance insaid buffer unit.
 4. The semiconductor manufacturing device of claim 1or 2 further comprising a measuring unit measuring the states of saidsubstrate treating substance in said buffer unit.
 5. The semiconductormanufacturing device of claim 1 or 2, wherein said buffer unit stores apredetermined amount of said substrate treating substance necessary forat least one substrate treating process in said substrate treatingchamber or said semiconductor manufacturing device, and is capable ofdelivering said substrate treating substance to either said substratetreating chamber or said semiconductor manufacturing device.
 6. Thesemiconductor manufacturing device of claim 1 or 2, wherein said bufferunit stores simultaneously at least two kinds of substrate treatingsubstances used by said substrate treating chamber, and is capable ofdelivering them to said substrate treating chamber.
 7. The semiconductormanufacturing device of claim 1 or 2, wherein said buffer unit reactssaid substrate treating substance, and stores said reacted substratetreating substance therein.
 8. The semiconductor manufacturing device ofclaim 3, wherein said control unit controls at least a temperature, apressure or a concentration of said substrate treating substance storedin said buffer unit.
 9. The semiconductor manufacturing device of claim4, wherein said measuring unit measures at least a temperature, apressure or a concentration of said substrate treating substance storedin said buffer unit.
 10. The semiconductor manufacturing device of claim1 or 2, wherein said substrate treating substance in said substratetreating chamber or said manufacturing device is a gas, a liquid or asolid necessary for the substrate treatment.
 11. The semiconductormanufacturing device of claim 1 or 2, wherein said substrate treatingsubstance is a cleaning gas for said substrate treating chamber.
 12. Thesemiconductor manufacturing device of claim 1 or 2 further comprising asecond buffer unit which recycles said substrate treating substancedischarged from said substrate treating chamber or said semiconductormanufacturing device, and returns the recycled substrate treatingsubstance to said substrate treating chamber or said semiconductormanufacturing device.
 13. A semiconductor manufacturing systemcomprising: an external source supplying a substrate treating substance;a semiconductor manufacturing device including at least a substratetreating chamber; a buffer unit receiving said a substrate treatingsubstance from said external source, storing it therein, and deliveringit to said substrate treating chamber or said semiconductormanufacturing device; and a control unit controlling the delivery ofsaid substrate treating substance from said external source to saidbuffer unit and the delivery of said substrate treating substance fromsaid buffer unit to said substrate treating chamber or saidsemiconductor manufacturing device.
 14. The semiconductor manufacturingsystem of claim 13 further comprising a computer-integratedmanufacturing system which thoroughly manages the delivery of saidsubstrate treating substance from said external unit, the receipt andstorage of said substrate treating substance in and from said bufferunit, and controls the operations of said semiconductor manufacturingdevice and said control unit.
 15. The semiconductor manufacturing systemof claim 14, wherein said computer-integrated manufacturing systemincludes a record-keeping database which records and manages anin-service schedule of the substance treatment and a manufactureschedule, and controls at least a delivery speed or a delivery order ofsaid substrate treating substance from said external source to saidsemiconductor manufacturing device via said buffer unit.
 16. A substratetreating method comprising: receiving a substrate treating substancefrom an external source, storing in a buffer unit said substratetreating substance necessary for at least one substrate treatingprocess, and delivering a predetermined amount of said substratetreating substance to a substrate treating chamber or a semiconductormanufacturing device provided with a substrate treating chamber.
 17. Asubstrate treating method comprising: delivering substrates into asubstrate treating chamber; receiving a substrate treating substancefrom an external source, storing in a buffer unit said substratetreating substance necessary for at least one substrate treatingprocess; and delivering a predetermined amount of said substratetreating substance to a substrate treating chamber or a semiconductormanufacturing device provided with a substrate treating chamber.
 18. Thesubstrate treating method of claim 16 or 17, wherein at least two kindsof substrate treating substances are simultaneously stored in saidbuffer unit.
 19. The substrate treating method of claim 16 or 17,wherein said substrate treating substance is reacted and is stored insaid buffer unit.
 20. The substrate treating method of claim 16 or 17,wherein at least a temperature, a pressure or a concentration of saidsubstrate treating substance stored in said buffer unit is controlled ormeasured.
 21. The substrate treating method of claim 16 or 17, whereinsaid substrate treating substances stored in said buffer unit are gases,liquids or solids.
 22. The substrate treating method of claim 16 or 17,wherein said substrate treating substances stored in said buffer unitare cleaning gases for said substrate treating chamber.
 23. Thesubstrate treating method of claim 16 or 17 further comprising:recycling said substrate treating substance discharged from saidsubstrate treating chamber or said semiconductor manufacturing device;storing said recycled substrate treating substance in a second bufferunit; and returning said recycled substrate treating substance to saidsubstrate treating chamber or said semiconductor manufacturing devicefrom said second buffer unit.